Electric generating system



H. D. MORTON.

ELECTRIC.GENERATING SYSTEM. APPLICATIOR FILED man. 1915.

Patented Oct. 7, 1919.

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HARRY D. MORTON, OF DETROIT, MICHIGAN.

ELECTRIC GENERATING SYSTEM.

Specification of Letters Patent.

Patented Oct. '7, 1919.

App11oatlon filed August 12, 1015. Serial Ila-45,17.

To all whom it may concern:

Be it known that I, HARRY D. Mormon, a citizen of the United States, and resident of Detroit, county of Wayne, State of Michigan, have invented certain new and useful Improvements in Electric Generating Systems, of which the following is a specification.

The purpose of this invention is to provide means whereby advantage may be taken of the desirable features of an engine of the Diesel type, for driving an electric generatorwhile at the same time eliminating some of the disadvanta es of such an engine.

Because of the fact t at the Diesel engine is from two to three times as eflicient as the best steam engine, and even more reliable than a steam engine, it is the ideal prime mover for driving an electric generator. It is, however, open to the objection of beinrr difficult to start-requiring, in its usua form,'for this purpose, the storagre of air at from 800# to 1,000# pressure. he engine itself is extremely simple, both in construc tion and in operation-eits complications being almost entirely such as are incident to the starting. I have devised means whereby such an engine may, when used for driving an electric generator, be readily started; and have accom lished this result without sacrificin the highly desirable features of Diesel e cienc economy and reliability. Incidentally, whereby an engine of this type when used for the purpose mentioned, may be simplified, and made even more eflicient than the usual Diesel engine.

In the drawing, I show diagrammatically the manner; in which my invention may be utilized for generating electric current, where an outside source of current, such, for instance, as that from a central electric station, is available for starting.

rrimarily. I accomplish this starting by employing the old and well known principle of drivinq as a motor the electric generator which is connected to the engine-using the central station current for this purpose. The converting .of the generator into an electric motor causes the engine to be rotated.

and started, whereupon the central station current is disconnected, and the engine thereafter runs under its own power and drives the generator. Thus means is provided whereby the user of a considerable amount of electricity may economically generate curhave also shown means rent with a rime mover at least as reliable as that use in the central station, which prime mover may be readilyand inexpensively started at any time.

Referring to the drawing, 10 designates the cylinder of an ordinary engine of the Diesel type in which a piston 11 works, the piston 11 bein suitably connected to a shaft 12. The hea of the engine 0 linder has a fuel inlet 13 which is control ed by a fuel valve 14 normall held to its seat by a sprin 15, one end of w -ich bears against the head of the valve 14 and the other end of which bears against the interior projections 16 on the valve casing 17. A trigger 18 is pivoted on the inside of the valve casing 17 and the lower end of said trigger engages the upper end of the valve 14 and prevents the .operaftion of the valve 14 until the trigger is tripped; The trigger has a nose 19 fitting a groove 20 at the lower end of an armature 21 also working in the valve casing 17. The armature 21 is held by means of a sprin 261 in a position below an opening 22 in the uel conduit 23.

The fuel conduit 23 is connected to a dome or liquid fuel container 25 in which the fuel is kept at a pressure from ,800 pounds to 1,000 dpounds, at which pressure it is delivere to the cylinder of the engine, throu h the valve casing 17 The dome 25 is on y partially filled with liquid fuel, the remainin space 251 therein constituting a reservo1r for air under pressure. The air enters the dome 25 through an inlet 252 which is connected by a pipe 253 to an air compressor 26, the shaft 261 of which may be connected to the engine shaft 12 by means'of any suitable ciutch 27, which is arran ed to be automatically operated when it is esired to start the engine.

The clutch 27 is automatically 0 erated by a clutch solenoid 28, the plunger 0 which is connected by a rod 281 and suitable lever 282 to actuate one of the members of the clutch'when the solenoid 28 is energized. The solenoid 28 is connected b a wire 29 tonne of the contacts of a switch 30 and when the switch 30 is closed the central sta-. tion power supply mains 31 and 32 are connected so as to supply current to the wires 29 and 33 whereby current is delivered to the local load circuit in which the solenoid 28. is located.

A Bout-don tube 34 is mounted on the dome 25 and is arranged to respond to the g 1,a17,osu

pressure in the dome and by means of links 341 it actuates a switch which is pivoted thereto and has contacts at 0 posite sides of one end to close the circuit between the switch terminals 36 and 37. The switch terminal 36 is connected by a wire 38 to the opposite side of the clutch soleno1d 28 and its terminal 37 is connected by a wire 39 to a divided circuit consisting of the branches 40 and 41. The conductor 40 leads to one side of a dynamo electric machine 42 the armature of which is mechanically connected to the engine shaft 12. The other brush of the electric machine 42 is connected to the wire 33.

The dome 25 has a relief outlet 254 which is controlled by a valve 43 on the lunger 44 of a solenoid 45, the terminals 0 which are connected by the wires 46 and 47 to the wires 39 and 33 respectively. When the solenoid is energized the valve 43 will close the openin 254 and when it is deenergized the spring 451 will force the valve 43 down, opening the dome 25 to the atmosphere and releasing the pressure therein. This is the normal condition of the apparatus while it is idle and consequently the Bourdon tube 34 will hold the switch member 35 thereof so as to normally connect the contacts 36 and 37. The Bourdon tube can also be arranged so that it will break the connection between the contacts 36 and 37 at any desired pressure at which it may be set. A fuel reservoir 48 is connected by a pipe 49 to a plunger chamber 50 in which the plunger 51 works. The plunger 1s reciprocated in the chamber 50 and derives its power from the shaft 12 and operates when the engine is running to force fuel or oil into the conduit 23 to replace that which is consumed in the operation of the engine so as to keep the fuel pressure substantially constant. The working pressure in the dome 25 is about 1,000 ounds per square inch and this pressure is communicated to the fuel or oil in the conduit 23, the pressure being retained therein by a check valve 501. On the up stroke of the plunger 51 the fuel oil passes by gravity through the pipe 49 into the chamber 50 and on t 1e down stroke of the plunger 51 the fuel oil is forced into the conduit 23 past the valve 501.

A byass 52 leads from the end of the pump c amber 50 back to the fuel reservoir 48. A valve 53 is located in the byass and normally closes the same, being held in closed position by a spring 531. The by-pass valve 53 is electrica. ly operated by meansofa magnet 54 which surrounds the valve casing and has one terminal thereof connected by the wire 55 to the wire 33 and has the other terminal. thereof connected by a wire 56 to a switch contact 57. The switch contact 57 is located opposite another switch contact 58 which is connected by a wire 59 to the conductor 39 and when the pressure in the dome 25 reaches a certain point the contacts 57 and 58 will be electrical] connected by a blade on the, switch mem r 35 and. the ma et 54 will be energized so as to operate t e valve 53 and open the bypass so that the fuel pumped by the plunger 51 will be returned to the fuel reservoir 48. Such a condition of operation may occur for instance when the engine is running idle or with a light load.

The wire 41 is connected to one terminal of a series solenoid 60 in series with the load on the line which may be designated by the lamp 61 connected between the conductors 62 and 33, the conductor. 62 being connected to the opposite end of the sole- H0161 winding 60. The plunger 63 of the solenoid 60 consists of a sleeve which has arms 631 at its lower end carrying rollers 64 adapted to engage the contacts 65 and 66. The sleeve 63 is splined to a shaft 67 which is rotated by the engine shaft 12. It will be seen that the contacts 65 and 66 will be periodically connected depending upon the speed of the engine and. Wlll energize the fuel'valve operating solenoid 68 one end of the windin of 'WlllCll is connected by the wire 69 to the wire 33, the other end of the'winding being connected by the wire 70 to the contact 66. The sleeve 63 is forced downwardly by a spring 601 and the extent to which it is raised de ends upon the cur rent assing through tlEe solenoid winding and t ierefore upon the load on the engine. The terminal 66 is of such a form as to correspond with the determined pull curve of the solenoid 60 and is shown as tapering upwardly so that the contact surface thereof becomes wider as the sleeve 33 and the roller carrying arm 631 is raised. Consequentlv for any particular load on the work circuit the sleeve 33 will assume a definite position in the solenoid 60 in which position the roller timer will close the circuit between the contacts 65 and 66 for the proper'length of time and the fuel valve 14 will be attracted as an armature by the solenoid 68. openlng said valve for such a period as to permit of sufficient fuel, entering the engine cyhnder 10 to carry the load on the work circuit.

The contacts 65 and 66 are curved and supported on the inner surface of an insu atmg cylinder (not shown). The contact 65 1s connected by a wire 71 to a switch contact 72 located 0p osite a switch contact 73 which 18 connecte to the wire 39 by a wire 74. When the air compressor has established a predetermined pressure in the dome 25, the circuit between the switch contacts 72 and 73 will be closed by the switch 35 so that current may flow to the solenoid 68 to operate the fuel inlet valve 1-1. The contact 57 is located a slight distance further 30, which supplies current to tie dynamo electric machine 42 to operate it as a motor,

the path of the current being as follows: positive supply main 31, swltch 30, com ductor 29, solenoid. 28, wire 38, switch contact 36, switch 35, switch contact 37, wires 39 and 40, electric machine 42, wire 33;

r and 37, or the air compressor mag switch30 and negative supply main 32. The solenoid 28 is simultaneously energized and clutches the shafts 12 and 261 together so that the electric machine 42 will drive the air compressor 26 and at the same time start the Diesel engine. The air compressor will continue supplying air to the fuel dome on the engine until a. predetermined pressure is reached at which the Bourdon tube 31 opens the circuit between the switch contacts 36 be stopped by opening the switch 30. imultaneously with the closing of the switch 30 the solenoid 45 is energized and its armature 4-iis attracted so as to close the opening 253.

Before the switch 30 is closed a portion of the load indicated by the lamp 61 has been thrown onto the work circuit and the solenoid 60 will therefore be energized proportionately to the current passing through it. The contacts 72 and 73 are connected by the switch 35 and a moment before the circuit to the contacts 36 and 37 is broken. The arm 631 carried by the plunger 63 will meanwhile have been raised, and will have assumed for the particular load on the work circuit a certain definite position with respect to the terminals 65 and 66 and the connecting of the contacts 72 and 73 by the switch 35 will close the circuit of the fuel inlet valve operating solenoid 68 by the following path: positive supply main 31, switch 30, wire 29, solenoid 28, wire 38, contact 36, switch 35, contact 37, wires 39 and 74, contact 73, switch 35, cont-act 72, wire 71, contact 65, rollers 64 and arm 631, contact 66, wire 70, solenoid 68, wire 69, wire 33, switch 30, to the negative supply main 32.

The period of time during which the solenoid 68 is energized and attracts its armature and the fuel valve 14 depends upon the portion of the contact 66 which the roller timer engages and the position of the latter is dependent upon the pull of the solenoid 60 which pull in turn depends upon the aml-ierage passing through said solenoid 60 or in other words upon the load which is on the work circuit, therefore the quantity of fuel admitted into'the engine cylinder is made automatically dependent upon the load carried b the work circuit. An appreciable length 0 time is required for the building up of the magnetic field in the solenoid 68, after its circuit is closed during which time the fuel valve 14 is progressively attracted as an armature. It is desirable that the fuel valve should open quickly and only when the magnetic field of the solenoid 68 has reached its maximum strength. The trigger .18 delays the openin of the fuel valve 14- by locking it in its 0 osed position. Meanwhile the armature 21 is progressively attracted by the solenoid 68 as the magnetic field is building up. As the armature 21 moves downward its tapered portion contacts with the nose 19 of the trigger 18 and at the moment the solenoid 68 attains its maximum strength the trigger 18 is forced from contact with the fuel valve 14 and the solenoid is allowed to quickly open the fuel valve and the inlet 13. When the timing mechanism breaks the circuit at the cont acts 65 and 66 the magnetic field of the solenoid 68 breaks down allowing the spring 15 to reseat the fuel valve 14. Simultaneously the spring 24 restores the armature 21 to its original position, the flange portion 201 of the armature 21 carrying the trigger 18 back to the position when it locks the fuel valve 14 in closed position.

The usual manner of controlling the speed of a Diesel engine is by means of a centrifugal governor acting upon a by-pass valve at the fuel pump. This method is open to two objections, (1) that the change in speed must actually have occurred before the corrective means can become operative and (2) that there is always a considerable quantity of fuel oil in the conduits between the oil pump and the fuel valve, which must be disposed of before the supply actuall delivered by the fuel valve is varied. t is apparent that the only scientific way of governing an engine of this type is by varying the length of time during which the fuel valve remains open as set forth above and at the same time maintaining a constant pressure through the fuel supply system.

In the usualv form of Diesel en ine the fuel valve is operated through a stu ng box by means of an arm. Inasmuch as the pressure in the fuel valve chamber ranges from 800 pounds to 1,000 pounds, there is always a likelihood of leakage through the stufling box. By arranging the fuel valve as an armature for the solenoid and forming the fuel valve chamber of some non-magnetic material, I am able to entirely inclose the fuel valve while at the same time keeping it connected directly with the high pressure fuel system.

\Vhen the fuel enters the engine the latter begins driving the electric machine 42 as a $216111)? and.- the latter sup lies current to t e electric circuit with whic it is connected. -When the engine has been started and the machine 42 is running as a generator the circuit between the contacts 36 and 37 is open and the solenoid 28 is consequently deenergized throwi out the clutch 27 and disconnecting the air compressor 26.

In order to prevent too high compression in the dome 25- during the o eration of the engine, as would occur if t e engine were carrying a light load, in which case the fuel valve would not be open long enough to per mit of its using fuel as fast as the pump 51 would sup ly it, I provide a by-pass 52 11 described. The valve 53 of the by-pass is operated by a solenoid 54 which is ener 'zed when the switch 35 closes the contacts 5 and 58. When the valve 53 is unseated oil flows through the by-pass 52 back to the fuel reservoir 4-8. This continues until the fuel valves have used suflicient oil to reduce to normal the pressure in the dome 25 whereupon the Bourdon tube 34 contracts, the circuit throu h the contacts '57, 58 is opened, the solenoid 54 is define!- gized, the valve 53 is resated b its spring 531 and the pump 51 again do ivers oil to the dome 25. The pump 51 will require only a small amount of energy for its 0 eration since it is only required to replenis the oil forced through the fuel valves, amounting to about one-half ound of oil er horsepower hour. Witht e ordinary iesel enine there is considerabie loss in efliciency us to the continual operation of the high duty air compressor, not only on account of the friction'of the larger parts in such compressor, but also because of the dissipation y storage of such air of the heat of compression. Since in the presentarrangement the air compressor is not operated continuousl but only to create the initial ressure in he dome, the 7 stem I have isclosed will show a higher egree of efliciency than the usual Diesel engine.

In the present arrangement also means is provided whereby it is impossible to raise the pressure in the dome to a dangerous oint and whereby the dome pressure havlng reached the predetermined maximum, the fuel valve operating mechanism is automatically brought into action resulting in the engine running under its own ower.

While I have herein shown and described the system in detail I do not wish to be limited to the exact construction disclosed as it is clear that various modifications may be resorted to without departing from the spirit of the invention.

Having thus described my invention what I claim and desire to secure by-Letters Patent is:

1. In a system of the class described, the combination of a Diesel engine, means for supplying fuel thereto, said means includ and adapted to operate as amotor or generator a circuit electrically connected to said e ectric machine, current supply means adapted to be electrically connected with said circuit and thereby operate said electric machine as a motor to start the Diesel engine, an air compressor for producing pressure in the pressure tank and means for connecting said compressor mechanically with the electric machine and engine when the circuit of the machine is connected with the current supply.

2. In a system of the class described, the combination of a source of current supply, an electric circuit, means whereby the electric circuit may be connected to the source of current suppl an engine, an electric machine adapte to operate either as a motor or as a generator, said electric machine being electrically connected to said electric circuit, an air compressor and means whereby said air com ressor is connected to be driven .by said e ctric machine when the electric circuit is connected to the source of current supply, said air compressor being adapted to be disconnected from said electric machine when the electric circuit is disconnected from the source of current supply. 4

3. In a system of the class described, the combination of power supply mains, an electric circuit, means whereby the electric circuit ma be connected to the power mains, a iesel engine having a cylinder provided with a fuel inlet, a fuel su ply tank connected to said inlet, an electric machine adapted to operate as a motor to start said engine and adapted to be operated by said engine as a generator to supply current to said electric circuit, an an compressor for supplying compressed air to said fuel supply tank, and means for automati' cally connecting said air compressor to the electric machine when the power mains are connected to said electric circuit and disconnecting said air compressor from said electric machine when the pressure in said tank has reached a predetermined maximum.

4. In a system of the class described, the combination of a Diesel engine having a controlled fuel inlet, a fuel supply tank connected to the inlet, means for starting the engine, an air compressor operable during starting for producing pressure in the fuel supply tank, and means for admitting fuel i of varying engine, a circuit containin overned bthe inlet and electrically operated means for controlling the passage of' fuel from the tank to the inlet, an e ectric circuit includ ing said control means and switch means the pressure within said tank or completing said circuit only when a predetermined pressure is present in the tank.

6. The combination with an engine, of .a partially filled fuel container connected to supply fuel to said engine, means for supplymg air under pressure to the space in said container above said fuel, means for supplying fuel to said container, and means for controlling the supply of fuel from said container to said engme.

7 The combination with an engine, of a fuel container connected to said engine, means for maintaining the fuel in said container at a substantially constant pressure, a fuel reservoir, means for feeding fuel from said reservoir to said container, a valve controlled by-pass to permit fuel to return to said reservoir when the fuel in said container exceeds a predetermined pressure, electric means for actuating the valve in said by-pass, electric means for. regulating the supply of fuel from said container to said engine, and means actuated by the ressure iIPSttld fuel container for contro ling the operation of said valve actuating electric means.

8. The combination with an engine, of a fuel container, a connection between said fuel container and engine, a valve in said connection and controlling the supply of fuel to the engine, electric means for operating said valve, and a timer switch actuated in response to the chan es of the load on said engine, said switch aving a contact electrically connected to said electric operating means, said contact having a contact surface I width so as to vary the length of time during which the fuel valve remains open in accordance with the variation in the load on the engine.

9. The combination with an engineof a fuel container connected to said engine, means for maintainin ressure in said container, an electric mac me connected to said said machine and a valve controlled by sai circuit for releasing the pressure in the container.

10., The combination with an engine of a fuel container connected to said engine,

fuel supply, and means for regulating the supply of fuel to said engine comprlsing a valve, means for operating said valve, releasable means for holding said valve to its seat, and means actuated by said operatin means for causing the release of sald hol in means to permit a quick opening of said va ve b said 0 rating means.

12. he com ination with an engine, of a fuel supply, and means for regulating the su ply 0 fuel to said engine comprising a va ve casmg, a valve 1n said casing, a solenoidoutside the valve casing for operating said valve, a releasable device in the casing for holding the valve to its seat, means n said casing actuated when said solenoid is .energized to operate said device after an interval of time whereby said valve will be opened suddenly when the pull of the solenoid is at its maximum, and means for restoring the parts when said solenoid is deenergized.

13. The combination with an engine, of a fuel supply therefor, means for regulating the supp y of fuel to said engine comprising a valve, means for operating said valve, and releasable means ositively holding said valve to its seat a apted to be released by said valve operating means after the latter becomes e'fl'ective on the valve, for the purpose set forth.

14. The combination with an engine, of a fuel supply therefor, means for regulating the supply of fuel to said engine comprisin a valve, releasable means for holdin sai valve to its seat, and a solenoid opera le on said valve and releasable means to release the latter after the solenoid has become substantially fully energized.

In testimony whereof I aflix my signature.

HARRY D. MORTON. 

